1. Field of the Invention
This invention relates to a vacuum cleaner of the type for household use.
2. Description of the Prior Art
Water bath vacuum cleaners typically include a main housing with a removably attached water bath pan. An intake opening in the water bath pan matingly engages an inlet in the main housing of the vacuum cleaner to allow dust and dirt entrained air to be ingested by a vacuum force through the inlet into the area defined by the water bath pan. The primary advantage of the water bath filter is that vacuum efficiency is not compromised as more dirt and dust is accumulated in the water bath, and no further filtering is viewed as necessary. The dust and dirt are trapped in the water bath as the incoming air is directed into the water bath pan and circulated within. Traditional filtering media allow the flow of air through the filtering media to be impeded by the accumulation of the dirt and dust that has collected thereon. However, just as traditional filter media will allow very tiny microscopic particles to escape capture, the water bath and separator may also fail to capture all of the very small or microscopic particles that are light enough to remain suspended in the air as the air is circulated in the water bath pan.
High efficiency filters, or HEPA rated filters, are used on vacuum cleaners in industrial and residential applications. These filters are made up of filter media with very tiny openings that are designed to capture the smallest microscopic particles that most traditional filter media or methods are incapable of capturing. The major drawback to the use of these types of filters is that due to the small size of the openings in the filter media, they capture all of the dirt and debris that hits them thereby clogging up very quickly, and requiring cleaning or replacement very often. For this reason, some vacuum cleaning products try to combine the HEPA rated filter with a more conventional dry filter media. The conventional dry filter media will capture the larger particles of dirt and debris, and the HEPA rated filter will only capture the smaller particles that escape the conventional dry filter media. The overall efficiency of the vacuum cleaner (and the conventional dry filter media) is affected as the air is redirected and routed through the additional filter. Also, the full area of the high efficiency filter is not utilized because the air is typically directed through a small opening in the main housing of the vacuum cleaner, which concentrates the flow of air on the portion of the high efficiency filter that is directly in front of the opening.
The present invention relates to a vacuum cleaner assembly comprising a main housing having an inlet and an outlet. A motor is disposed within the main housing between the inlet and the outlet for providing motive force to a cooling fan, a blower, and a separator. The cooling fan is mounted within the main housing above the motor to circulate cooling air around the motor. A baffle is mounted within the main housing for directing the cooling air around the motor, and to filter the air that is circulated around the motor before that air is exhausted. The blower is mounted within the main housing below the motor for drawing air into the inlet and exhausting air outwardly through the outlet. The separator is mounted below the blower for circulating the air and water within a water bath and providing, in combination with the water bath, a primary filter for filtering the air prior to exhausting the air outwardly through the outlet. A second filter assembly including a high efficiency filter, known as a HEPA rated filter, for filtering microscopic dust and dirt particles that escape the separator and water bath and may be disposed after both the water bath and the separator and before the outlet to atmosphere for additional filtering of the air prior to being exhausted. The second filter assembly may also include a third filter comprising a carbon impregnated filter of a reticulated foam or similar material for absorbing or trapping odors drawn from the air, including smoke and fish odors. The second filter and the carbon impregnated filter are disposed in a recess which is integral with the main housing allowing for direct and efficient flow of the air through the water bath, separator, second filter, and carbon impregnated filter. In an alternative embodiment, the second filter can be a non-HEPA filter used in combination with the carbon impregnated filter.
Accordingly, the present invention will utilize the separator and water bath filter to capture the larger particles of dirt and debris prior to routing the air through the second, HEPA rated or non-HEPA rated filter to capture microscopic particles that escape the water bath, and finally through the carbon impregnated filter to absorb or trap odors. The recess for the high efficiency filter is located integrally to the main housing allowing the air to flow directly from the water bath canister through the second filter and the carbon impregnated filter with minimal redirection of the air and no noticeable impact on the primary filter. This will allow the air to flow smoothly through the series of filters. The second filter assembly will not be overly clogged because the separator and water bath will capture the majority of the larger dust and dirt particles before the air goes through the second filter assembly. The recess is designed to allow the majority of the surface area of the high efficiency filter to be in the direct line of airflow thereby the overall efficiency of the vacuum cleaner is maximized.